Answer:
The fifth line contains the error.
Step-by-step explanation:
Line 1 is the equation.
Lines 2, 3, and 4 are correct.
The error is in the 5th line.
The square root of a negative number is not a real number, so if this problem is solved only with real numbers, there is no solution.
If imaginary numbers are allowed, then the last line should read:

We have the function
and we want to find a function that has the same y-intercept than the previous function.
First, let's find the y-intercept by subtituting 0 for 'x'.

Now that we found that y-intercept =-3, any lineal function of the type:
will have the same y-intercept. Where 'a' can take all the real values.
Also, any quadratic function of the type:
will have the same y-intercept. Where 'a' and 'b' can take all the real values.
Let the actual distance be x mile.
1/4 inch = 1/2 mile
9/2 inch = x mile
(9/2)/(1/4)=x/(1/2)
18=2x
x=9
the actual distance is 9 mile.
64
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